<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
<style type="text/css">
body {
	background-color: black;
	margin: 0; /* 去掉自带外边距 */
}

img {
	position: absolute;
}
</style>
</head>
<body>
  <script type="text/javascript" src="../js/jquery-1.4.2.js"></script>
  <script type="text/javascript">
			//开启添加雪花的定时器
			setInterval(function() {
				//创建雪花图片
				var img = $("<img src='snow.png'>");
				//设置随机雪花大小 40-80
				var size = parseInt(Math.random() * 21) + 20;
				//获取窗口宽度
				var w = $(window).width();
				//得到一个随机的left值
				var left = parseInt(Math.random() * (w - size));
				img.css({"width" : size + "px","left" : left + "px"});
				$("body").append(img);
				var h = $(window).height();
				//让雪花图片移动到屏幕下方20-40 2000-4000
				img.animate({"top" : (h - size) + "px","left":left+200+"px"},size*100).fadeOut(1000,function(){
					img.remove();
				});
			}, 10);
		</script>
</body>
</html>












